secondarries - ZR-1 Net Registry Forums

Hib Halverson · 04-04-2013

It is true that the port throttles are open anytime the engine is is at WOT, however, anything below 90% TPS (ie: "almost WOT") that's not the case. Below 90% TPS, SPT opening strategy varies according to TPS and RPM.

Stock or near stock 350s need port throttles to have good driveability and good torque at high part throttle in the lower RPM ranges.

Highly modified 350s may not need them and drag race-only 350s don't need them. Also, any engine modified by someone who doesn't give a s@@t about performance/drivability other than at WOT/high-rpm doesn't need them.

368s which are otherwise stock or near stock may not need them.

Bigger than 368s...rip 'em out.

If you're takin' 'em out, and you're actuators are good, send them to me.

04-04-2013	#19
Hib Halverson Join Date: Jun 2005 Location: CenCoast California Posts: 898	Re: secondarries It is true that the port throttles are open anytime the engine is is at WOT, however, anything below 90% TPS (ie: "almost WOT") that's not the case. Below 90% TPS, SPT opening strategy varies according to TPS and RPM. Stock or near stock 350s need port throttles to have good driveability and good torque at high part throttle in the lower RPM ranges. Highly modified 350s may not need them and drag race-only 350s don't need them. Also, any engine modified by someone who doesn't give a s@@t about performance/drivability other than at WOT/high-rpm doesn't need them. 368s which are otherwise stock or near stock may not need them. Bigger than 368s...rip 'em out. If you're takin' 'em out, and you're actuators are good, send them to me. __________________ Hib Halverson Technical Writer former owner 95 VIN 0140 current owner 19 VIN 1878 Last edited by Hib Halverson; 04-04-2013 at 11:56 PM. Reason: added content